Chesapeake Veterinary Cardiology Associates, seven practices in Maryland and Virginia; cvcavets.com. CVCA doctors see the most veterinary cardiac cases of any such practice in the country. By referral only.

Iams Pet Imaging Center, 328 Maple Ave. E., Vienna; 703-281-9440; iamspetimaging.com. The nation’s first animal MRI facility and the only one in the Washington area.

Regional Veterinary Referral Center, 6651 Backlick Rd., Springfield; 703-451-8900; vetreferralcenter.com. Offers a full range of medical specialities, with particular experience in oncology. Also the home of Radiocat, a quick and effective treatment for feline hyperthyroidism.